app.js

function login() {
  location.href = "email.html";
}

// ========login/logout on single page=========
// var flag = sessionStorage.getItem("mail");
// const element = document.getElementById("log");
// if (flag) {
//   if (element) element.innerText = "LogOut";
// } else {
//   if (element) element.innerText = "LogIn";
// }

var allmail = [];
var userMailData = localStorage.getItem("UserDataEmail");
if (userMailData !== null) {
  allmail = JSON.parse(userMailData);
}

function genMail() {
  var mail = document.getElementById("mail");
  //   console.log(mail.value);
  if (mail.value === "") {
    alert("Please enter email");
  } else if (!mail.value.includes("@")) {
    alert("please includes '@' in the email adrress");
  } else if (!mail.value.includes(".com")) {
    alert("please enter a part following '@'");
  } else {
    sessionStorage.setItem("mail", mail.value);
    var isEmailExist = allmail.includes(mail.value);
    if (!isEmailExist) {
      // email = mail.value;
      console.log(mail.value);
      allmail.push(mail.value);
      localStorage.setItem("UserDataEmail", JSON.stringify(allmail));
    }
    if (isEmailExist) {
      location.href = "passlogin.html";
    } else {
      location.href = "PassCreate.html";
    }
  }
}

var allpass = [];
var userPassData = localStorage.getItem("UserDataPass");
if (userPassData !== null) {
  allpass = JSON.parse(userPassData);
}
function createpass() {
  var newPass = document.getElementById("newPass").value;
  var conPass = document.getElementById("conPass").value;
  if (newPass === "") {
    alert("All field Required");
  } else {
    if (newPass !== conPass) {
      alert("Password not match, \nEnter same password on both field ");
    } else {
      allpass.push(newPass);
      localStorage.setItem("UserDataPass", JSON.stringify(allpass));
      location.href = "user.html";
      var logvalue = document.getElementById("log").innerText;
      console.log(logvalue);
    }
  }
}

function loginpass() {
  var mail = sessionStorage.getItem("mail");
  var pass = document.getElementById("pass").value;
  var isPassExist = allpass.includes(pass);
  var match = true;
  if (isPassExist) {
    for (var i = 0; i < allmail.length; i++) {
      if (allpass[i] === pass && allmail[i] === mail) {
        location.href = "user.html";
        var logvalue = document.getElementById("log");
        console.log(logvalue);
        match = false;
      }
    }
    if (match === true) {
      alert("Password is incorrect");
    }
  } else {
    alert("Password is incorrect");
  }
}

function loadfun() {
  var mail = sessionStorage.getItem("mail");
  document.getElementById("para").childNodes[1].innerText = mail;
  // var log = sessionStorage.getItem("log");
}

function sell() {
  location.href = "sell.html";
}

function forSell() {
  alert("SignIn Required to post your product ads");
}